From my own experience WD40 is rubbish for drilling and taping, go and get yourself a tin of special grease (usualy about 10quid for a massive tin which will last for aaages).
Tin is white with bright orange stripe somewhere. Can check it tomorrow if you want.
Does the job fine for me qbazdz & is also excellent for getting marker off the metal



So, I put the case on it's side with the io shield in.

Took my last pc & placed it in the case.

Held it up enough to have the io bits fit inside the shield & drawn along the edge & with the edge being drawn I could remove the io shield.


Then line the board up to the line & poke a marker through to get the exact mounting positions, then spot drilled, then drilled, then tried tapping but the tap fell straight through



Then put the standoffs in.



Tadaaa & wooooo hooooooo











Now all I need to do is drill & file the expansion slots in the mobo panel.
Also I pre-drilled the positions for the fan mount bars.